Pricing & Investment Guide
How Much Does Radon Mitigation Cost?
A standard sub-slab depressurization system in East Tennessee typically runs $1,600 to $1,800, plus diagnostic testing. But the honest answer is that cost depends on your foundation type, how much sealing your home needs, and how the system has to be routed. Here is a full, transparent breakdown.
It's More Than Just the System Itself
When homeowners ask what radon mitigation costs, most companies quote a fan and some pipe. That is only part of the job. At Rn86 Solutions, every slab-on-grade or basement installation starts with diagnostic testing to confirm mitigation will actually succeed, and to determine exactly how powerful the system needs to be, before any pipe is installed.
That diagnostic step is called Pressure Field Extension (PFE) testing, and it's the foundation of a system engineered to solve your radon problem the first time, not just equipment installed and hoped for the best.
What PFE Testing Tells Us
- ✔ Whether mitigation will succeed at your home
- ✔ The exact fan size and power required
- ✔ Whether a second suction point is needed
- ✔ The most effective suction pit location
Why We Test Before We Build
PFE testing ($300) is a diagnostic step, not an upsell. Here's exactly what it does for your system.
Low Suction Readings
If PFE testing shows low suction across the slab, we know upfront that a larger, more powerful fan is required. This is decided before installation, not discovered afterward.
No Communication
Occasionally, testing shows no communication across the slab at all. That tells us we need a second suction point, or in some cases a different mitigation method entirely.
One Flat Price, Any Fan
We charge the same installation price no matter which fan your home needs. PFE testing lets us select the right fan upfront, so a bigger fan never means a bigger bill.
Cost by Service
Actual pricing depends on your foundation type and site conditions. These are the typical ranges we quote across East Tennessee.
| Service | Typical Cost |
|---|---|
| PFE Diagnostic Testing | $300 |
| Sub-Slab Depressurization — Slab-on-Grade Home | $1,600 – $1,800+ |
| Sub-Slab Depressurization — Basement Home | $1,600 – $1,800+ |
| Crawlspace Vapor Barrier Encasement | $3 – $4 per sq. ft. |
| Mitigation System After Crawlspace Encasement | $1,600 – $1,800 |
| Multifamily, Per Affected Unit (Slab) | $1,600 – $1,800 per unit |
| Initial Radon Test (48-Hour) | $225 |
| Post-Mitigation Verification Test | $225 |
Slab-on-Grade & Basement Homes
Both slab-on-grade and basement homes with a concrete slab fall into the same sub-slab depressurization range: $1,600 to $1,800. Where you land in that range depends on how much pipe is needed to safely vent soil gas outside the home and how complex the routing is.
Crawlspace Homes
Crawlspaces are priced differently because the process is different. Before we can create the low-pressure zone that keeps soil gas out, we fully encase the crawlspace floor with a vapor barrier at $3 to $4 per square foot, depending on size, height, and barrier thickness. The mitigation system installed afterward is priced the same as a standard system, $1,600 to $1,800.
Multifamily & Apartment Properties
Multifamily buildings are priced per unit, not per building. It's common to find only one or two units out of eight testing high on a slab property. We only mitigate the units that need it, at the same $1,600 to $1,800 range as a single-family home.
Testing, Before and After
An initial 48-hour radon test is $225. The post-mitigation verification test is also $225 and includes our return trip to retrieve the monitor after a 48-hour delay and 48-hour test period, roughly 96 hours after installation.
What Can Increase Your Cost
Extensive Sealing Needs
Slabs with a lot of cracks, gaps, or an unsealed sump pit need more material and time to seal. Every unsealed gap bleeds off suction, weakening the pressure field across the slab.
Interior vs. Exterior Routing
Exterior routing is generally less expensive because the pipe run is simpler. Roof penetrations, especially on steep rooflines, can add cost due to shingle damage risk and sometimes require bringing in a roofer.
Skipping PFE Testing
Without PFE testing done first, we often have to cut multiple suction holes about a foot apart across the slab to create enough air pathways, far more labor and material than one correctly placed suction pit.
No Slab Communication
On the rare occasion PFE testing shows no pressure communication at all, a second suction point or a different mitigation method may be needed. This is determined during testing, before your quote is finalized.
Radon Mitigation Cost FAQ
How much does radon mitigation cost in Knoxville or Nashville?
A standard sub-slab depressurization system for a slab-on-grade or basement home typically costs $1,600 to $1,800, plus $300 for PFE diagnostic testing. Crawlspace homes require vapor barrier encasement at $3 to $4 per square foot in addition to the mitigation system.
What is Pressure Field Extension (PFE) testing and why does it cost extra?
PFE testing is a $300 diagnostic step that measures whether a mitigation system will successfully pull soil gas from under your entire foundation. It determines the correct fan size and confirms mitigation will work before installation begins, which prevents underpowered systems and costly rework.
Does a bigger or more powerful fan cost more?
No. Rn86 Solutions charges the same price regardless of fan size. PFE testing determines which fan your home needs, and that's factored into your quote upfront rather than charged as an add-on.
How much does crawlspace radon mitigation cost?
Crawlspace mitigation requires encasing the crawlspace floor with a vapor barrier first, priced at $3 to $4 per square foot depending on size, height, and barrier thickness. The mitigation system installed after encasement is priced the same as a standard system, $1,600 to $1,800.
How much does radon mitigation cost for an apartment or multifamily building?
Multifamily mitigation is priced per unit, not per building, at $1,600 to $1,800 per affected unit for slab foundations. It's common for only one or two units in a building to test above the EPA action level, and only those units require mitigation.
How much does a radon test cost?
An initial 48-hour radon test is $225. A post-mitigation verification test, which confirms the installed system reduced radon levels, is also $225 and includes a return trip after a 48-hour delay and 48-hour test period.
What makes radon mitigation more expensive than the base price?
The most common factors are extensive slab sealing needs, interior versus exterior pipe routing, roof penetrations on steep rooflines, and skipping PFE testing. Without PFE testing, installers often need to cut multiple suction holes about a foot apart to create adequate air pathways, which significantly increases labor and material costs.
Get an Accurate Quote for Your Home
Every home is different. The most reliable way to know your exact cost is to start with PFE testing and a professional evaluation from Rn86 Solutions.